The present invention relates to a pocket-sized device for photocopying and printing parts of texts, diagrams, or images. The device according to the invention makes it possible to sample a phrase in a text, an equation, or a diagram, and to recopy these elements on paper to retain them, because of their interest for the user.
Photocopying is a very widespread means of reproduction at this time, but it does not enable partial reproduction of a document except on the condition that the portions of the document that are not to be reproduced are masked, or that the portion of interest is cut out of the complete photocopied document. On the other hand, the dimensions of the photocopying equipment must be compatible with those of the document to be photocopied and of the base material receiving the copy. Finally, although known photocopying equipment, even the most sophisticated, is sometimes portable, it is not truly pocket-sized; it cannot be carried on one's person, for instance in a pocket.
The subject of the invention is a miniaturized device, having a bulk and volume such that its user can have it with him at all times in his pocket, like a wallet. This device has at least two faces: a first face including an optical matrix pickup, which by traveling along in front of the document to be reproduced picks up the data and puts them into memory. A second face includes a matrix printing head, such as a dot matrix printing head. When the part of the document to be photocopied has been picked up by the optical pickup and put into memory, turning the device according to the invention over makes it possible to print this part onto a base material by means of the matrix printing head.
This pocket-sized device thus makes it possible to retain a quotation in a text, or a diagram and to take notes by means of partial localized photocopying, by posting them on a sheet of paper or a laboratory notebook, for example. Thus pickup and reading are effected, followed by the reproduction of only that portion of the document of which reproduction is desired.
The reading pickup, which effects the optical pickup of the portion of the document, also assures the electrical conversion of the optical signal: this is a linear pickup of the charge transfer device type, also know as a charge coupled device. This pick-up, which has a matrix structure, determines a line in the document, and each cell of the matrix identifies a zone of this line on the document and furnishes an electrical signal corresponding to white or black or half tones with a dynamic that enables retaining the features of the image.
The electrical signals emitted by the CCD matrix are read in parallel or serially and transferred to a memory in which they are stored. Whether reading is parallel or serial depends on the organization of the memory.
For printing the part of the document that has been read, the partial photocopying device is turned over. The data stored in memory are transferred to a matrix printing head, by way of an amplifier with multiplexing after the amplifier; the printing head has the same matrix structure as the CCD pickup and memory.
The time base or clock, in the course of all these operations, is furnished by a system of wheels, at least two in number, of which one wheel rolls without sliding on the document and the other rolls without sliding on the reproduction base material. These wheels, which have the same characteristics, are associated with known devices that furnish electrical pulses, corresponding to the reading--or writing--intervals, and the width of each interval is equal to the width of one line read by the CCD pickup.